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1.
Environ Pollut ; 310: 119892, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35932895

RESUMO

The interactions of plastics and soil organisms are complex and inconsistent observations on the effects of plastics on soil organisms have been made in published studies. In this study, we assessed the effects of plastic exposure on plants, fauna and microbial communities, with a meta-analysis. Using a total of 2936 observations from 140 publications, we analysed how responses in plants, soil fauna and microorganisms depended on the plastic concentration, size, type, species and exposure media. We found that overall plastics caused substantial detrimental effects to plants and fauna, but less so to microbial diversity and richness. Plastic concentration was one of the most important factors explaining variations in plant and faunal responses. Larger plastics (>1 µm) caused unfavourable changes to plant growth, germination and oxidative stress, while nanoplastics (NPs; ≤ 1 µm) only increased oxidative stress. On the contrary, there was a clear trend showing that small plastics adversely affected fauna reproduction, survival and locomotion than large plastics. Plant responses were indifferent to plastic type, with most studies conducted using polyethylene (PE) and polystyrene (PS) plastics, but soil fauna were frequently more sensitive to PS than to PE exposure. Plant species played a vital role in some parameters, with the effects of plastics being considerably greater on vegetable plants than on cereal plants.


Assuntos
Plásticos , Solo , Ecotoxicologia , Plantas , Poliestirenos
2.
Transl Anim Sci ; 5(3): txab107, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34430799

RESUMO

Within Australia, approximately 6.4% of total greenhouse gas emissions are from animal methane (CH4) derived from enteric fermentation. Mitigation of ruminant CH4 is a key concept in support of sustainable agriculture production; dietary manipulations a viable strategy to lower CH4 release during enteric fermentation. In order to determine the effects of dose response of biochar and wood vinegar supplementation on fermentation parameters and CH4 production, this study utilized in vitro batch culture incubations. It is hypothesized that the addition of either biochar or wood vinegar will successfully reduce enteric CH4 emissions without negative modification of other fermentation parameters. Three feed substrates (vegetable mixed ration, maize silage, and winter pasture) were separated into treatments containing either biochar at 0%, 0.5%, 1%, 2%, and 4% DM replacing substrate (w/w basis), or wood vinegar at 0%, 0.25%, 0.5%, 1%, and 2% into incubation media volume (v/v). At 6, 12, and 24 hours after inoculation, total gas volume, and methane (CH4 %) were measured. Volatile fatty acid (VFA) concentrations, media pH, and in vitro dry matter digestibility were measured at 24 hours. Biochar at various dosages had no effect (P > 0.05) on fermentation characteristics other than decreased in vitro dry matter digestibility (IVDMD; P = 0.01) at 2% and 4% (DM basis) inclusion. Similar to biochar, dose response of wood vinegar had no effect on in vitro fermentation characteristics. However, feed substrate had major effects on all fermentation parameters (P = 0.01) where winter pasture > vegetable mixed ration > maize silage for all recorded fermentation characteristics. Biochar and wood vinegar supplementation were ineffectual in mitigating CH4 production or modifying fermentation characteristics, thus rejecting the initial hypothesis. These results suggest the use of biochar is not an effective tool for methane mitigation in ruminant livestock and infers that studies previously reporting success must better define the systemic mechanisms responsible for the reduction in CH4.

3.
Front Psychol ; 12: 719476, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002830

RESUMO

Purpose: This study aims to explore the effects of entrepreneurship education by examining the influences of the curriculum system, teaching team, design of practical programs, and the institutional systems on universities' entrepreneurial education performance. Design/Methodology/Approach: This paper employs a case-based approach-Qualitative Comparative Analysis (QCA). Data were collected from 12 universities that were typical cases in the implementation of entrepreneurial education. The four dimensions of entrepreneurship education are applied as conditional indicators. fsQCA3.0 software is used to analyze the necessary conditions and condition combination of the truth table. Findings: There are three sets of condition combinations of the intermediate solution that results in a high level of entrepreneurial education performance: (1) when the credit ratio of entrepreneurship courses is higher and there are more practical platform platforms, even if the entrepreneurship education system and mechanism is less mature, the level of entrepreneurial education performance is high; (2) with a higher credit ratio of entrepreneurship courses, higher quality of teaching teams, and higher standard of practical platforms, the level of entrepreneurial education performance is high; (3) with a higher level of credit ratio of entrepreneurship courses and more practical platforms, as well as mature entrepreneurship education system and mechanism, even if the quality of the teaching team is lower, the level of entrepreneurial education performance is satisfied. Research Limitations/Implications: The dimensions of entrepreneurship education can be expanded; additionally, given that there are many other factors affecting entrepreneurial performance, it is necessary to identify and integrate other possible factors on an ongoing basis. Practical Implications: This study offers practical implications for universities and policy makers that can promote the transformation of theoretical knowledge into practice in the field of entrepreneurship in colleges and universities. Social Implications: This study is one of the first to empirically examine the effect of institutional-driven entrepreneurship education in developing countries. The enhancement of entrepreneurship education can benefit the development of individuals and schools, and even has a potential impact on the progress of the country and society as a whole. Originality/Value: This study emphasizes the significance of viewing the entrepreneurial education as a multi-dimensional concept by targeting different kinds of players. Furthermore, it employs a case-based approach to identify configurations of the antecedent attributes of the curriculum system, teaching team, design of practical programs, and the institutional systems, and their influence on universities' entrepreneurial education performance.

4.
Front Microbiol ; 10: 2599, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803152

RESUMO

Ensiling vegetables with forage crops is a suggested method of waste diversion and can be directly utilized as a livestock feed. Carrot or pumpkin, ensiled at 0, 20, or 40% dry matter (DM) with crop sorghum, and with or without a second-generation silage inoculant were assessed for nutritive composition, organic acid profiles, aerobic stability and in vitro rumen fermentation characteristics. The study was a completely randomized design, with the fixed effects consisting of vegetable type (carrot vs. pumpkin), level (i.e., the level of vegetables), inoculant (inoculant or non-inoculant) and the interactions, and mini-silos within treatment as the random effect. The experimental unit for sorghum treatments represented by each mini-silo (5 kg capacity). Silage was sampled after 70-days ensiling for nutrient composition, 14-day aerobic stability, organic acid profiles and microbial diversity. After 24 h in vitro incubation, rumen fermentation parameters were assessed, measuring gas and methane (CH4) production, in vitro digestibility and volatile fatty acid concentrations. Sorghum ensiled with carrot or pumpkin at 20% or 40% DM increased crude fat (P ≤ 0.01) and decreased (P ≤ 0.01) silage surface temperature upon aerobic exposure compared to the control. Bacterial communities analyzed through 16S rRNA gene sequencing linearly increased (P ≤ 0.01) in diversity across both vegetables when the vegetable proportion was increased in the silage; dominated by Lactobacillus species. ITS analysis of the fungal microbiota upon silage opening and after 14 days (aerobic stability) identified increased (P ≤ 0.03) fungal diversity with increasing vegetable proportions, predominantly populated by Fusarium denticulatum, Issatchenkia orientalis, Kazachstania humilis, and Monascus purpureus. Upon assessment in vitro, there was an increase (P ≤ 0.04) in in vitro digestibility and some CH4 parameters (% CH4, and mg CH4/g DM), with no effect (P ≥ 0.17) on remaining CH4 parameters (mL CH4/g DM, mg CH4/g digested DM), gas production or pH. However, increasing vegetable amount decreased percentage of acetic acid and increased percentage of propionic acid of the total VFA, decreasing A:P ratio and total VFA concentration as a result (P ≤ 0.01). The results from this study indicate including carrot or pumpkin at 20 or 40% DM in a sorghum silage can produce a highly digestible, microbially diverse and energy-rich livestock feed.

5.
Sci Rep ; 9(1): 13183, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515497

RESUMO

Incorporation of carrot or pumpkin at 0, 20 or 40% dry matter (DM-basis) with crop maize, with or without a silage inoculant was evaluated after 70 days ensiling for microbial community diversity, nutrient composition, and aerobic stability. Inclusion of carrots or pumpkin had a strong effect on the silage bacterial community structure but not the fungal community. Bacterial microbial richness was also reduced (P = 0.01) by increasing vegetable proportion. Inverse Simpson's diversity increased (P = 0.04) by 18.3% with carrot maize silage as opposed to pumpkin maize silage at 20 or 40% DM. After 70 d ensiling, silage bacterial microbiota was dominated by Lactobacillus spp. and the fungal microbiota by Candida tropicalis, Kazachstania humilis and Fusarium denticulatum. After 14 d aerobic exposure, fungal diversity was not influenced (P ≥ 0.13) by vegetable type or proportion of inclusion in the silage. Inoculation of vegetable silage lowered silage surface temperatures on day-7 (P = 0.03) and day-14 (P ≤ 0.01) of aerobic stability analysis. Our findings suggest that ensiling unsalable vegetables with crop maize can successfully replace forage at 20 or 40% DM to produce a high-quality livestock feed.


Assuntos
Ração Animal , Fungos/crescimento & desenvolvimento , Lactobacillus/crescimento & desenvolvimento , Microbiota , Silagem/microbiologia , Verduras , Zea mays
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